Collapsible container



Dec. 17, 1963 H. G. QUASE coLLAPsIBLE CONTAINER Filed Feb. 28, 1963 INV EN TOR HAROLD G. QUASE BY M 6% United States Patent Oil'ice 3,114,458 Patented Dec. 17, 1963 3,114,468 v CGLLAPSIBLE CONTAINER harold G. Quase, Kensington, Md., assigner to Under- Water Storage, Inc., Washington, D.C., a corporation of Maryland Filed Feb. 2S, 1963, Ser. No. 263,374 17 Claims. (Cl. 2208) This invention relates to a container, which is expandible and collapsible for large volume or large storage capacity varlation in use.

The term large volume variation, as it is used herein, relates to the variation between collapsed and expanded container volumes, and not to any particular capacity dimension. These containers can be of any regular shape but are usually cylindrical.

-In accordance with this invention the containers side walls may be formed of magnetic structural material either of magnetic iron or any other durable wall material that includes a means to impart a magnetic effect thereto. Thus, other magnetic materials such as laminates which include magnetic metal sheets or magnetic metal particles mounted in the structural wall material may also be used.

The wall construction of my container is of controlled thickness with respect to the magnetic force associated therewith as to lbe slightly resilient under these magnetic forces of attraction between contiguous movable sections of container wall so that they are resiliently biased toward each other into a firm uid tight seal. Tha-t is, mating wall sections contiguous with each other are held sufliciently tightly pressed together to be self-sealed by the force of their mutual magnetic attraction against leakage of liquids or gases within or without the container.

Containers constructed according to this principle, therefore, have wall sections which are movable relative to each other to allow expansion and contraction of an enclosed volume. These wall sections, by being magnetically attracted to each other, remain sealed against leakage of gas or liquids within or without the container as the volume of the container is expanded or contracted.

-In the usual use of a container of this invention, the sectional construction can be expanded, responsive to internal pressure of fluids, such as liquid or gas, pumped into the container. The container may be collapsed by external pressures of liquid about the outside o-f the container. For instance, the former effect allows expansion of volume by the internal fluid pressure of gas or liquid forced into the container. The latter eifect can result merely by external pressure of liquid about the outside of the container such as when the containers are used for storage under water, so that the containers are collapsed under the surrounding hydrostatic pressure upon the outside of the container merely by withdrawing the liquid or gas from the inside of the container. Similarly, when the container is used for storage in open air, iitV may be collapsed by reducing the pressure inside of the container to below atmospheric pressure conditions.

It will be appreciated, therefore, that the container is collapsible by external pressure on the outside of the container by reducing the pressure Within sufficiently below that of the external pressure to overcome the magnetic stabilizing forces of attraction between the wall sections of the container by which they are held, assembled and sealed. That collapse of the container from expanded to reduced volume condition can, as stated, be effected by drawing a vacuum Within the container, but usually it will be collapsed merely by withdrawing the supporting internal pressure of the fluid content with which it is filled. The latter effect is always available in a preferred emplacement of such container under Water as an underwater storage facility, whereby Withdrawal of the gaseous or liquid content of the container allows a collapse of the 2 container to reduced volume by the surrounding hydrostatic pressure.

In the drawings:

FIGURE 1 shows a typical tank in an expanded, completely filled form, the taper of the wall sections being exaggerated to illustrate the assembled construction;

FIGURE 2 shows the tank in a collapsed condition;

FIGURE 3 shows a detail of a solenoid locking device; and

FIGURE 4 shows a rdetail of a modilied construction illustrating the mounting of an extraneous magnetic ring near the ends of mating sections.

Referring tothe drawings, the tank assembly 1 is formed of annular, usually cylindrical sections 12, 14, 16 and 1S, each comprising a section having tapered walls, as exaggeratedly shown in FIGS. Vl and 2, to matingly and slidingly t each about the next upper section and within the next lower section of the series. The uppermost annular section ring 18 comprises a -top section having a continuing `closure top 20, and the lower section I12 continues into a bottom closure 22 which seals the combination section at the bottom. That bottom section 22 may extend beyond the annular Wall section 12 as at 24 forming an extending flange portion which may be fastened as by bolts 26 into a permanent mounting such as a concrete bed 2S. That bed support 28 may be any anchoring means, such as underwater piles (not shown) or upright beam legs (not shown) for support of the tank at any storage site.

Referring to FIGURES 3 and 4, the tank walls of magnetic substance, as above defined, are closely machined, one section 12, 14, 16 or 18, to slidingly fit nestingly, each within the next lower section. The outer Wall surface of a section is magnetized to comprise one pole of a magnet, such as a north pole of a magnet, indicated in FIGURES 3 and 4 by the letter N, and the inner container wall of each s-ection is the opposite pole such as south, indicated by the letter S. The walls per se are of sufiiciently flexible material selected of sufficiently ythin dimensions to be urged magnetically into sealing contact, one wall section with the next, by the magnetic attraction between the wall positions, even in sliding movement, one upon the other. For instance, referring to FIGURES 3 or 4, the wall portions 32 are both magnetic and are contiguously assembled with their poles in mutually attractive sealing relationship. The south pole of wall Bfil is in sliding contact with north pole of wall 32, whereby the walls, sufficiently flexibly constructed, form a fluid-tight seal therebetween. The upper end 34 of a wall section 30 is tapered to a knife edge at the point of contact with the mating wall 32, whereby in sliding contact, the knife edge 34 tends to remove dust, grit, rust or other accumulated impurities on the wall 32 to maintain a fluid-tight magnetic iit under the magnetic force therebetween.

` The container 10 may have suitably fitted therein ducts and valves, such as a duct 36 controlled by valve 38, and/ or a duct 40 controlled by valve 42 or an upper venttype duct 44 controlled by valve 46. Fluid materials to be stored may pass into the container through any such selected duct; for example duc-t 36 with valve 3S is opened to allow fluid to enter, as shown in the collapsed condition of the container in FIGURE 2, and continuous passage of fluid to be stored through said duct 3o will causeV expansion of the container by the sections sequentially sliding apart while maintaining the magnetic `seal to prethrough duct 36 will force the expansion by its internally exerted hydraulic pressure so 4that the container -will be sufficiently expanded to house whatever quantity of gas or liquid is supplied for storage therein. When such container is mounted under water, the liquid can be withdrawn either through duct 36 controlled by valve 3S or duct 40 controlled by valve 42, and the surrounding hydraulic pressure of liquid in underwater storage will collapse the container from the position in FIGURE 1 ultimately to the position of FIGURE 2, as the fluid is withdrawn. In the filling or discharging, the valves can be automatically and remotely controlled as desired.

Moreover, where the container is not to be used under water, the fluid can be withdrawn as described, from duct 40 controlled by valve 42, and the fluid contents may be released by opening an air venting duct 44 controlled by valve 46. Thereafter, the contents may be Withdrawn by gravity How or by pum-p, but the container will not collapse except by closing of duct 44 and Valve 46 and reducing the pressure within the container below atmospheric, The tendency to draw a vacuum through line 4t) by pump suction can cause the container to collapse from the form of FIGURE 1 to that of FIGURE 2, or to any intermediate position as the fluid is withdrawn, by the atmospheric pressure differential upon the container due to suction induced by any pump in line 40 (not shown).

Moreover, the container can be used for dry storage. For instance, it may be inated from the collapsed condition of FIGURE 2 to the expanded condition of FIGURE 1 by pumping a gas such as air through duct 36, valve 38 being open with other valves closed, and thereafter the dry solids, such as grain, can be filled into the expanded container through any manhole opening such as may be provided by a plate 4S, usually mounted in one of the sections such as upon the top 20. In a preferred manner for emptying the grain-filled tank, the solids are removed by any conventional air-carrier line (not shown) which will suspend the solids in a gas, thereby emptying the container. The emptied container can then be collapsed from the position of FIGURE l to FIGURE 2 by closing plate 48 and drawing a vacuum through a duct 36, controlled by valve 38.

Thus, in broadest aspect, my container system may comprise mutually attractive to sealed condition magnetic wall sections, slidable one within the next, to a closed collapsed condition maintaining its seal as the wall sections move. The wall materials, while conventionally of magnetic metal, such as magnetic iron, are closely machined to a sliding seal fit, one section within the next. The container sections may be formed of various structural materials having magnetic materials imbedded therein to supply sufficient magnetic force to have a resilient magnetic seal in sliding t. For instance, the structural materials may be laminated, some sheets of Which may be of magnetic metal or of reinforced plastic containing magnetic particles. The metal wall portions, moreover, may have non-magnetic or other metals clad thereon such as by plating or laminating for other structural strength, bearing surface, or corrosion resistive purposes. For instance, the magnetic metal may carry a paint or ceramic coating or have applied a rust resistant coating or other metal coatings for any desired properties. For instance, it may be useful to coat a magnetic metal with copper or aluminum or to coat a soft metal such as babbitt as a bearing metal for ready sliding seal of a container section of one surface against the next. That seal is generally enhanced by keeping the sliding surface clean by knife edge 34.

In a modification, as shown in FIGURE 3, the container sections may be locked in open position by a series of solenoids Si), each carrying an armature S2 which can be extended or retracted within the solenoid body 5t), responsive to energizing current remotely through lines 54. In the locking position of FIG. 3, the extended armature 52 will pass entirely through a bore 56 in a wall 30 but will lock in a shallow groove 58 of the mating wall 32. In that position the container is mechanically locked against any external pressures whatever the external pressure may be and the container will remain in expanded position. For instance, in a locked position as shown in FIGURES 1 and 3, the container may be mounted under water and emptied or filled while in the expanded condition as desired. Thus the use of solenoids, while they are optional, provides wider flexibility in the use of the container in water or on land.

Moreover, while the wall material is generally selected and sized to be flexibly urged into fiuid tight seal, where extraordinary large fluid pressures may be encountered, such as storage of compressed gases under abnormally high pressures, it is sometimes useful to include extraneous seals. For this purpose, sealing rings such as ordinary rubber or fiber rings 60 can be embedded in annular grooves running around each mating wall section near the upper or lower edge to provide such extra sealing effect.

In a further modification, greater magnetic strength elements are sometimes usefully applied for imparting a stronger seal for purposes similar to that just described. Such extra magnetic strength may also be useful to supplement particular structural materials having low magnetic strength or to impart greater sealing flexibility under applied magnetic pressure. As shown, in FIGURE 4, a magnetic ring 62 is mounted about the outer wall 30 as a magnetic element. That ring 62 maybemrfufcient magnetic strength to be the sole source of magnetic strength in the structure, applying its sealing magnetic force, as shown in FIGURE 4, against an inner section 32 of magnetic material, magnetically responsive thereto. That magnetic ring 62 structure of FIGURE 4 may be used in combination of extraneous sealing elements 60, as shown in FIGURE 3, so that the mating edges of two sections 3f) and 32 may be sealed by a combination only of a magnetic ring 62 and conventional fiber sealing elements 60. Of course, as described above, the walls 3() and 32 may also be of magnetic materials so that all three or two of the sealing means are used in combination.

The sealing elements may be of synthetic as Well as natural rubber, including silicone rubber. Moreover, the seal can include foamed rubber and plastics, which can be filled with sealing uids. For instance, a useful sealing effect can be imparted by inclusion of surface active substances which will tend for an emulsion at the oil and water interface at the edge of the seal, which will improve the sealing effect as well as lubricate the movement of the sealing element. Such surface active substance can be any common emulsifying agent such as sodium lauryl sulfate.

As shown in FIGURE 2, several stops 64 may be placed near the lower portion of each lower section s0 that the upper ring portion sliding therein can descend to rest upon the stop as shown in FIGURE 2.

As thus described, a collapsible tank 10 is provided having magnetically sealed walls which collapse nestingly or expand to substantial container form in continuous fluid-tight sliding fit of at least two sections. Various modifications will occur to those skilled in the art. As stated, the only magnetic element may be the ring 62 of magnetic metal or an electro magnet remotely controlled; or, only one of the mating wall sections may be magnetic and the other merely magnetically responsive, but unmagnetized.

The container may be used under water or on land. It may be expanded or collapsed by merely putting fluid into the container or removing from the expanded container; or it may be expanded or collapsed by extraneously applied hydraulic or gas pressures. The containers can be mounted under water or on land suitably fitted into concrete anchors or upon other suitable supporting means, 01 they may even be mounted portably on trucks or other vehicles.

Accordingly, it is intended that the description herein given be regarded as illustrative and not limiting, except as defined in the claims.

This application is a continuation-in-part of application Serial Number 68,558, filed November 10, 1960.

I claim:

1. A collapsible container of variable volume between expanded and collapsed condition comprising a series of annular slidably interlitting wall sections and magnetic seals between movable contiguous wall sections, said magnetic seals comprising magnetic elements distributed annularly about mating edges of said Wall sections, magnetically biasing said mating edges' into fluid-tight sealing engagement with each other, whereby the container is magnetically fluid-tight.

2. A collapsible container of variable volume between expanded and collapsed condition, said container comprising several annular tapered sections slidably interlitted, whereby the upper mating annular wall sections fit nestingly within lower wall sections, magnetic means supplying magnetic forces between the slidable sections urging adjacent wall portions together into Huid-tight sealing lit, said wall sections being sufficiently flexible to form a Huid-tight sealing fit therebetween, responsive to the applied magnetic force.

3. A collapsible container of variable volume between expanded and collapsed condition, said condition comprising several slidably inter-fitting annular ring sections of magnetic substance whereby the wall sections are mutually attracted by the magnetic forces therebetween into sealing pressure contact, said sections being flexibly responsive to the magnetic forces to form a uid-tight seal therebetween.

4. A collapsible container of a variable volume between expanded and collapsed condition, said container comprising several slidably intertting annular ring sections, said sections comprising magnetic metal arranged to exert a mutually attractive force therebetween, to form a sliding fluid-tight seal between the sections both in expanded and collapsed condition.

5. The container as defined in claim 4 having at least one valve-controlled duct means communicating with the interior whereby to supply and discharge fluids from the container.

6. The container as defined in claim 4 having at least one valve-controlled duct means, and means to supply and withdraw fluid from the container under pressure whereby to vary the internal liuid pressure within the container sufiiciently above atmospheric to expand the 6 container by fluid pressures therein, and sufficiently below the surrounding external pressure on the container to cause collapse thereof.

7. Container as defined in claim 4 wherein tie walls are formed of magnetically responsive material sufiiciently resilient under the magnetic forces to bias them together into fluid-tight seal therebetween.

8. A collapsibe container of variable volume between expanded and collapsed conditions comprising a series of annular slidably interfitting Wall sections comprising magnetically responsive materials and magnetic means mounted adjacent to the ends of the lower sections biasing contiguous portions into a fluid-tight seal therebetween.

9. The container as defined in claim 8 wherein the magnetic means comprises a magnetic ring mounted near the end of an annular wall section.

l0. T he container as defined in claim 4, further having locking means associated with the ends of an annular wall section securing said sections to a contiguous section.

1l. The container as defined in claim 10 in which the locking means comprises a locking bolt slidable between contiguous sections to secure them stably in expanded position.

12. Container as defined in claim 11 in which the sliding locking bolt comprises an armature or a solenoid, operable electrically from a point remote from the site of the container to electrically lock and release sections tor expanded to collapsed positions.

13. Container as defined in claim 4 having a manhole opening for supply of dry substance for storage therein.

14. Container as defined in claim 4 wherein the wail material is formed, at least in part, or non-magnetic substance having magnetically responsive metal associated therewith.

15. Container as deiined in claim 1 having additional extraneous sealing means mounted between contiguous sections.

16. The container as defined in claim 1 including resilient sealing means between magnetically biased wall sections.

17. The container as defined in claim l including resilient sealing means between magnetically biased wall sections, said sealing means including a surface active agent adapted to facilitate emulsion formation between immiscible liquids within and outside of said container.

References Cited in the tile of this patent UNITED STATES PATENTS 2,990,970 Murdock July 4, 1961 

1. A COLLAPSIBLE CONTAINER OF VARIABLE VOLUME BETWEEN EXPANDED AND COLLAPSED CONDITION COMPRISING A SERIES OF ANNULAR SLIDABLY INTERFITTING WALL SECTIONS AND MAGNETIC SEALS BETWEEN MOVABLE CONTIGUOUS WALL SECTIONS, SAID MAGNETIC SEALS COMPRISING MAGNETIC ELEMENTS DISTRIBUTED ANNULARLY ABOUT MATING EDGES OF SAID WALL SECTIONS, MAGNETICALLY BIASING SAID MATING EDGES INTO FLUID-TIGHT SEALING 